Exhaust cover



Oct. 29, 1968 A. M WESTERMAN 3,407,720

EXHAUST COVER Filed Jan. 5, 1967 I 27 3?, FIGURE 4 i m l l 25 26 3| 30 v4 0. i 41 26 23 23 25 21! f l 22' 2" l l l 22 39 ff 323 f 55 |6 le# l I -32 x V' /E l lgw 17,4: l n 2o |9\E |4 )I9 |5`f v|9 I E SJ FIGURE 5 25 I2 27 l 33 3| 4l l" n 43o 24 4 I3 .l1-'H i. "n 38 23/ 1 l l "8 FIGURE 2 l @HO Alberi M. Wesermon,

l 9 1 N VENTOR.

t I5y l United States Patent Olhce 3,407,720 Patented Oct. 29, 1968 3,407,720 EXHAUST CGVER Albert M. Westerman, E. 10122 Broadway, Spokane, Wash. 99206 Filed Jan. 3, 1967, Ser. No. 606,855 Claims. (Cl. 98-59) ABSTRACT 0F THE DISCLOSURE A cover movably associated with a mounting structure adapted to mount the cover over the top of a substantially vertical exhaust pipe to prevent entry of debris into the exhaust channel. The cover opens in response to exhaust gas pressure and has associated catch mechanism to prevent opening in response to physical forces external to the exhaust channel, such as wind.

My invention relates generally to a cover for vertical exhaust pipes and more particularly to such a cover that is pivotably mounted to open to allow normal exhaust escape but may not be opened by wind forces external to the exhaust pipe.

Many vehicles and machines having vertical or substantially vertically oriented exhaust pipes normally stand without cover during operation and oftentimes for extended storage periods. During such periods natural moisture, particularly rain, snow and the like, is relatively free to enter the exhaust pipe and be conveyed to some degree therethrough to the operating mechanism of the machine. This condition is not desirable because of the deleterious physical effects it may have upon the machine.

In response to the problem various caps have become known to prevent the ingress of debris through the exhaust pipe.

Such caps as are known are kgenerally moveably mounted, for vertical or pivotable motion, to allow escape of exhaust gases, when present, from about the cap. Generally such caps have been biased to a normally closed position and are automatically opened by pressure of the exhaust gas. Manually operated caps have not been popular because of the effort involved in initial opening and the high probability of forgetting to close the cap upon cessation of use.

In the use of known automatically opening caps, it is generally possible for a wind of normal force, appropriately directed, to open the cap other than in response to exhaust gas pressures. If the cap be so opened, especially during an extended storage period, there will be no notice of it by an operator and the cap will cease to serve its purpose. With these thoughts in mind the instant invention was conceived to provide a cap not operable by the wind. In so doing it is:

A principal object of my invention to provide a cover for a vertically oriented exhaust pipe, having a pivotably mounted cap biased to a normally closed position but openable automatically by exhaust gas pressure, with auxiliary means of maintaining said cap in a closed condition against external Wind forces exerted thereon.

A further object of my invention to provide such a cover that has external means of manually opening said cap, other than by pressure of exhaust gases from inside said exhaust system.

A still further object of my invention to provide such an exhaust cover that prevents substantially all physical debris from entering the exit orifice of a substantially vertically oriented exhaust pipe including particularly various naturally occurring aqueous matter.

A still further object of my invention to provide such a device that is of new and novel design, of simple and economic manufacture and operation, of durable and rugged nature, and one that is otherwise well adapted to the uses and purposes for which it is intended.

These and other objects of my invention will become apparent from consideration of the following specification and the accompanying drawings which form a part of this application. In carrying out the objects of my invention, however, it is to be understood that its essential features are susceptible of change in design and arrangement with only one preferred practical embodiment being illustrated and specified, as required.

In the accompanying drawings, wherein like numbers of reference refer to similar parts throughout:

FIGURE l is a vertical orthographic side view of my invention in closed condition upon the upper exit orifice of a vertical exhaust pipe.

FIGURE 2 is a similar view of the same device illustrated in FIGURE 1, shown in. an open condition.

FIGURE 3 is an orthographic plan View of the invention illustrated in FIGURE 1 showing its various parts, their configuration, and arrangement from this aspect.

FIGURE 4 is a medial vertical cross-sectional view of the invention of FIGURE 3, taken on line 4--4 thereon in the direction indicated by the arrows.

FIGURE 5 is a medial vertical cross-sectional view of the invention of FIGURE 3, perpendicular to that of FIGURE 4, taken on the line 5-5 on FIGURE 3 in the direction indicated by the arrows thereon.

Referring now to the drawings in greater detail and particularly that of FIGURE l, it will there be seen that my invention comprises generally the mounting structure 10 pivotably mounting external covering cap 11 and internal catching cap 12 manually operable through opening means 13. The invention is releaseably positioned about the uppermost exit orifice 14 of a. substantially vertically oriented exhaust pipe 1S `operatively carried by some machine l(not shown).

Mounting structure 10 comprises cylindrical body 16 of such size and configuration as adapted to fit about the outer peripheral surface of exhaust pipe 15. This body preferably is provided with plural vertical slits 17 allowing it to be more readily deformed to t securely about an exhaust pipe, especially if there be some slight size variance, and at least one horizontal slit 18 in its upper part above its communication with exhaust pipe 15 to allow small amounts of air or exhaust gas to pass through the exhaust system without the opening of external covering cap 11. A narrow cylindrical band 21 is provided about the upper extension of the outer periphery of body 16 to provide a shoulder 22 formed by the upper surface of body 16, to receive the internal cap 12; this band and body are preferably rigidly joined by welding or similar structural attachment. The body is fastened in place on exhaust pipe 15 by cooperating fastening band 19 and tightening nut-bolt combination 20 adapted to elastically deform the lower portion of cylinder body 16 to increase its frictional engagement with the exhaust pipe.

L shaped cap support arms 23 are structurally attached to upper band 21 of the body member to project upwardly and rearwardly therefrom to provide a pivot support for the caps 11, 12. Appropriate paired opposed holes are rovided in the -upper ortion of the vertical extension `of the cap support arms to pivotably receive the covering cap axle.

External covering cap 11 includes disk-like cover 25, of a radius somewhat greater than that of upper band 21 of the mounting structure 10, so that lip 26 projects laterally outward thereover. This lip is desirable to prevent ingress of water through the upper opening of band 21 but in cap structures not embodying my invention this feature is deleterious because it provides a horizontal surface of which upwardly directed wind forces may operate to open the covering cap.

The covering cap structurally communicates with upwardly and laterally extending pivot arm 27. In the instance illustrated this pivot arm is shaped in a crosssectional U form from sheet metal. Appropriate holes 2S are provided in this member to cooperate with holes in cap support arms 23 to pivotably mount the unit. Downwardly depending catch cap mounting arm 29 is provided in the lower part of pivot arm 27, lateral of the mounting structure, to provide for pivotable support of the catch cap.

`Opposed slots 24 are provided in the mounting arm to receive `adjustable weight 37 releasably positioned relative the slots by nut-bolt combination 40, to allow variation of the eccentric mass of the member about its pivot point and thusly to vary the force of exhaust gases required to open the cover. 1

Pivot arm 27 is pivotably supported between cap support arms 23 by bolt 30, extending through the holes in the cap support arms and holes 28 in the pivot arm, and maintained in position by cooperating nut 31. This mounting is preferably by releasable means to provide for simple manufacture, assembly and replacement of parts.

Internal catch cap 12 includes circular disk-like cover 32 of a configuration similar to that of the body of mounting structure 1f), and of a size to allow the member to fit within the inner periphery of upper band 21 but rest upon and be supported from below by shoulder 22, as illustrated particularly in the cross-sectional view of FIG- URE 4. Curved catching dog 33 structurally communicates with the undersurface of cap 32 in its forward extension. The dog must be so configured in its downward extension and so spaced in its forward extension to allow upward pivotable motion of cap cover 32 about its pivotable mounting.

Disk weight 41 is movably mounted by eye 42 on the central lower surface of the catch cover to prevent undesirable fluttering or vibration of this member, particularly in response to variation in pressure of exhaust gases.

The rearward portion of the catch cover communicates with bell crank-like raising arm 34 pivotably mounted between opposed cap mounting arms by axle 35 extending through holes 36 in the mounting arms and cooperating holes in the raising arm. `Preferably the raising arm projects between the legs of the pivot arm for cover of the member but the handle portion 38 of the arm must project rearwardly beyond the raising arm for manual manipulation. These requirements result generally in a bell crank type structure as illustrated.

A hole 39, configured and positioned to allow passage of cap mounting arms 29, is provided in the upper portion of band 21 and body 16, as the case may require to allow the depending catch mounting arms to move pivotably within the body 16 when the cover cap is raised.

With the foregoing description of the structure of my invention its operation can be understood.

The external covering cap structure is designed as shown in FIGURE l, to protect the upper orifice of exhaust pipe when in a normally closed position. The member is pivotably mounted on arm 27 by bolt 30 and is formed so that the structure is slightly overbalanced to a closed position by greater weight on the forward side of the pivot point. `Obviously other mechanical means of so biasing the structure might serve the purpose of my invention, if not so simply or so well.

External cover 11, when it opens, pivots about axle 30; at the same time catch cover 32 will pivot about axle 35. As illustrated, there is greater redial distance between the forward lower surface of catching dog 33 and axle 30 than there is between this member and axle 35. With axle 35 on the same frame and offset from axle 30, axle 35 will tend to pivot in a forward direction upon pivotable motion of the cover cap tending to open. Obviously then, if the catch cap be in its normally lowered position and any external force be exerted upon the covering cap structure 11 tending to open it, the covering cap will be prevented lfrom opening by the lower forward surface of catching dog 33 of catch cover 32 coming into engagement with the upper internal surface of'body 16 of the mounting structure. If cover 11 is to be raised, the catching cap 12 must first be raised so that it may not come into engagement with body 16. This may be done by upward pressure of exhaust gases presented through exhaust pipe 15 or by manual manipulation of the handle 38 of raising arm 34.

Catch cap 32 is similarly biased by an eccentric mass to a downward position with catch dog 33 extending below axle 35. Obviously, again such biasing might be by other mechanical means known in the art.

It is to be noted from the foregoing description of my invention that when the external cover of my. invention is in its normally biased closed position it will maintain the upper exit orifice of a vertical exhaust pipe free from ingress of debris.

It is further to be noted that the cover will remain in closed position against external forces until such time as the auxiliary catch cover be raised from its normally biased position, either manually or by forces within the exhaust system.

The foregoing description of my invention is necessarily of a detailed nature so that a specific embodiment of it may be set forth, as required, but it is to be understood that various modifications of detail, rearrangement and multiplication of parts may be resorted to without departing from its spirit, essence or scope.

Having thusly described my invention, what I desire to protect by Letters Patent, and

What I claim is:

1. In a compound exhaust cover adapted to be maintained in closed condition against external force on a substantially vertically oriented cylindrical exhaust system, the improvement comprising:

a mounting structure carried by the upper part of an exhaust system with a cap support arm extending thereabove;

a first external covering cap, biased to operatively cover the upper orifice of said exhaust system, mounted for upward pivotal motion, on an axle carried by the cap support arm laterally from and above the exhaust system;

a catch cap pivotably mounted upon said exhaust system radially inward of said covering cap mounting, said catch cap being carried within the internal pe` riphery of said exhaust system and having a depending catching dog to engage said internal periphery upon pivotable motion of said system about said covering cap pivot but not on motion about said catch cap pivot; and

means for limiting the maximum motion of said covering cap relative to said catch cap.

2. An exhaust cover or the nature aforesaid, for use with a substantially vertically oriented exhaust pipe, comprising, in combination:

a cylindrical mounting structure releasably positionable on the uppermost part of a substantially vertically oriented exhaust pipe and extending thereabove with a catch cap shoulder therein;

a cap support arm communicating with said mounting structure and extending laterally thereabove;

an external covering cap covering the upper vertical orifice of said mounting structure, having an upwardly extending support arm pivotably communicating with the upper lateral portion of said cap support arm, said covering cap support arm being mechanically biased to a normally closed position but pivotably moveable thereform;

a catch cap, pivotably mounted on said support arm radially inward of said cover cap mounting, carried under said covering cap and within the internal periphery of said mounting structure and supported the catch cap shoulder against vertical motion therebelow, said catch cap having a forward depending catching dog configured to engage said mounting structure upon upward pivotable motion of said cover cap but not on upward pivotable motion of said catch cap, the said cover cap being mechanically biased to a normally `closed position; and

means for limiting the maximum motion of catch cap relative to the covering cap.

3. The invention of claim 2 wherein said cap support arm is mechanically biased to a normally closed position by a weight adjustably positionable to vary the eccentric mass of said covering cap structure.

4. The invention of claim 2 wherein the means of limiting motion of the catch cap relative 'the covering cap is further characterized by -a central eye on the lower surface of said covering cap extending through a slot in References Cited UNITED STATES PATENTS 2,694,358 11/ 1954 Taylor 98-59 2,749,832 6/ 1956 Harmon 98--59 2,983,216 5/ 1961 Stadge et al. 98-59 3,216,343 11/1965 Farr 98-59 3,274,917 9/1966 Tolbert.

3,334,932 8/ 1967 Buresh 292-87 ROBERT A. OLEARY, Primary Examiner.

M. A. ANTONAKAS, Assistant Examiner. 

